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The programme opens with a recreation of Rontgen' s original experiments in which he observed the effects of x-rays on a fluorescent screen. Stuart Freake appears on the scene and he gives an expl...anation of Rontgen's experimental set up. He then explains that almost 13 years later, X-rays were shown to be part of the electromagnetic spectrum, giving a boost to the newly emerging quantum theory. Graham Farmelo introduces us to the X-ray spectrum of molybdenum at various voltages and argues that the characteristic lines could not be explained by classical physics. The similarity with spectral lines in the visible spectrum is made. Graham gives a resume of various atomic models, ending on the Bohr model and its idea of electron energy levels. The hydrogen atom is used to explain visible spectra, and by comparing the energy levels of molybdenum with hydrogen, a near identical process is seen to occur in the generation of characteristic x-ray lines. The story is taken a stage further by a brief resume of Mosley''s work on X-ray spectra, in which he linked atomic number to nuclear charge. All this happened with 20 years of Rontgen's discovery. The next 20 years vras to see an equally startling revolution, but the idea of energy levels was here to stay.
The programme opens with a recreation of Rontgen' s original experiments in which he observed the effects of x-rays on a fluorescent screen. Stuart Freake appears on the scene and he gives an expl...anation of Rontgen's experimental set up. He then explains that almost 13 years later, X-rays were shown to be part of the electromagnetic spectrum, giving a boost to the newly emerging quantum theory. Graham Farmelo introduces us to the X-ray spectrum of molybdenum at various voltages and argues that the characteristic lines could not be explained by classical physics. The similarity with spectral lines in the visible spectrum is made. Graham gives a resume of various atomic models, ending on the Bohr model and its idea of electron energy levels. The hydrogen atom is used to explain visible spectra, and by comparing the energy levels of molybdenum with hydrogen, a near identical process is seen to occur in the generation of characteristic x-ray lines. The story is taken a stage further by a brief resume of Mosley''s work on X-ray spectra, in which he linked atomic number to nuclear charge. All this happened with 20 years of Rontgen's discovery. The next 20 years vras to see an equally startling revolution, but the idea of energy levels was here to stay.
| Module code and title: | S271, Discovering physics |
|---|---|
| Item code: | S271; 11 |
| First transmission date: | 18-08-1982 |
| Published: | 1982 |
| Rights Statement: | |
| Restrictions on use: | |
| Duration: | 00:24:00 |
| + Show more... | |
| Producer: | John Stratford |
| Contributors: | Graham Farmelo; Stuart Freake |
| Publisher: | BBC Open University |
| Keyword(s): | Atomic modules; Bohr module; Molybdenum; Mosley; Quantum theory; Reconstruction of Rontgen's experiments |
| Master spool number: | HOU3585 |
| Production number: | FOUS173X |
| Videofinder number: | 1790 |
| Available to public: | no |
